What if the ISPs don't have the space to 'retain' the data? They most likely need to cut costs like everyone else, why should they have to shelve out money for equipment and upkeep that they don't want or even need? To me this is like requiring the phone company to keep records on how many minutes you rack up, and what numbers you connect to. If those things are out of the norm, they investigate you.
If IPRED guidelines suspects a user is abusing their connection in some way, THEN they should contact the ISP, and run an investigation on them. To me it's just an excuse to run mass sweeps on the collected data in an effort to find people who have 'unique' internet usage. I just have a thing against abusing peoples privacy. This reminds me, recently we heard of a few hackers breaking into databases of health care facilities. What ever happened with that?